Mercury-201

Properties and data of the isotope ²⁰¹Hg.

Contents

General Data

Parent Nuclides

NMR Data

Isotones und Isobares

Literature

Mercury-201 is a stable isotope of the chemical element mercury, which has 121 neutrons in its atomic nucleus in addition to the element-specific 80 protons; the sum of the number of these atomic nucleus building blocks results in a mass number of 201.

The identification of Hg-201 as a distinct isotope was reported in 1925; it was subsequently confirmed by mass spectra [1].

See also: List of individual Mercury isotopes (and general data sources).

General data

Name of the isotope:Mercury-201; Hg-201Symbol:²⁰¹Hg or 20180HgMass number A:201 (= number of nucleons)Atomic number Z:80 (= number of protons)Neutrons N:121Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.5125 (= neutron-proton ratio)Neutron excess (N-Z):41Isotopic mass:200.970303(5) u (atomic weight of Mercury-201)Nuclide mass:200.9264214 u (calculated nuclear mass without electrons)Mass excess:-27.66258 MeVMass defect:1.704154396 u (per nucleus)Nuclear binding energy:1587.40959495 MeV (per nucleus)
7.89756017 MeV (average binding energy per nucleon)Separation energy:S_N = 6.2306(6) MeV (first neutron)
S_P = 7.711(27) MeV (first proton)Half-life:stableSpin and parity:
(nuclear angular momentum)3/2-Magnetic dipole moment:μ(μ_N) = - 0.5602257(14)Charge radius:5.4581(32) femtometer fmYear of discovery:1925

Parent Nuclides

Direct parent isotopes are: ²⁰¹Tl, ²⁰¹Au.

Occurrence

Comparison of the natural Mercury isotopes including isotopic abundance (mole fraction of the isotope mixture in percent):

	Atomic Mass m_a	Quantity	Half-life	Spin
Mercury Isotopic mixture	200.592 u	100 %
Isotope ¹⁹⁶Hg	195.96583(2) u	0.15(1) %	stable	0+
Isotope ¹⁹⁸Hg	197.966769(3) u	10.04(3) %	stable	0+
Isotope ²⁰⁰Hg	199.968327(3) u	23.14(9) %	stable	0+
Isotope ²⁰²Hg	201.970643(5) u	29.74(13) %	stable	0+
Isotope ²⁰⁴Hg	203.973494(3) u	6.82(4) %	stable	0+
Isotope ²⁰¹Hg	200.970303(5) u	13.17(9) %	stable	3/2-
Isotope ¹⁹⁹Hg	198.968281(3) u	16.94(12) %	stable	1/2-

NMR data

Nuclear magnetic properties and parameters of the NMR active Nuclide ²⁰¹Hg

Isotope:²⁰¹Hg-NMRQuantity:13.17(9) %Spin:3/2-Nuclearmagnetic moment
μ/μ_N:- 0.5602257(14)Gyromagnetic ratio γ:0 · 10⁷ rad T^-1 s^-1
0.00000 MHz T^-1Nuclear g-factor:g_l = -0.3734838Quadrupole moment Q:+ 0.387(6) barn (100 fm²)Resonance frequency:v₀ = 2.8469 MHz at 1 TRelative Sensitivity:[related to ¹H = 1.000]:
0.00149 (H₀ = const.)
0.3343 (v₀ = const.)

Nuclear Isomers

Nuclear isomers or excited states with the activation energy in keV related to the ground state.

Nuclear Isomer	Excitation Energy	Half-life	Spin
^201mHg	766.22(15) keV	94(2) μs	13/2+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 121) and isobaric (same nucleon number A = 201) with Mercury-201. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 121	Isobar A = 201
73	¹⁹⁴Ta
74	¹⁹⁵W
75	¹⁹⁶Re
76	¹⁹⁷Os	²⁰¹Os
77	¹⁹⁸Ir	²⁰¹Ir
78	¹⁹⁹Pt	²⁰¹Pt
79	²⁰⁰Au	²⁰¹Au
80	²⁰¹Hg	²⁰¹Hg
81	²⁰²Tl	²⁰¹Tl
82	²⁰³Pb	²⁰¹Pb
83	²⁰⁴Bi	²⁰¹Bi
84	²⁰⁵Po	²⁰¹Po
85	²⁰⁶At	²⁰¹At
86	²⁰⁷Rn	²⁰¹Rn
87	²⁰⁸Fr	²⁰¹Fr
88	²⁰⁹Ra	²⁰¹Ra
89	²¹⁰Ac
90	²¹¹Th
91	²¹²Pa